Every year since I’ve been gardening here in the southeastern USA, my garden has been visited by one or more large, colorful, web spinning spiders. I call them “zipper spiders”, because of the zipper-like structure in the middle of their webs, but they’re more commonly called the “black and yellow garden spider”.
“Argiope aurantia” is the scientific name of this particular arachnid, and its bite is supposedly harmless to humans, although I can assure you I have absolutely no intention of finding out if this is true or not! Spider bites aren’t something to fool with. Several years ago my best friend got bit on the foot by what we assume was a brown recluse, and he wound up in the hospital for several days, getting pumped full of steroids. Besides, “harmless” in many descriptions of this spider is compared to a bee sting, and I don’t know about you, but I prefer NOT to be stung by bees.
I really don’t like spiders, (besides the previously mentioned episode my friend had with the brown recluse, I have bad memories of shaking off spiders that would get stuck on me while I was hiking through the woods – ugh!!), and in most cases if given a chance I’ll squash them, but so far these “zipper spiders” and I have been able to co-exist. They are pretty, and they eat bugs, so I leave them alone. And in turn, they leave me alone! I can weed around a web without one bothering me, which is a good thing, because they can move fast! But trust me, one bite, or one bad experience, and they’re toast. I’ll shoot them with wasp spray!
They spin large sprawling webs. The technical term for that “zipper” in the middle of the web is “stabilimentum”, (run that word past your local know-it-all!), and no one really knows what its purpose is. The webs seem strong, as do the spiders themselves, but inevitably one day in early fall both spider and web just disappear, (beamed up to the mothership?), leaving behind a few forlorn ragged strands of silk. According to Wikipedia, (so this may or may not be true), the spider eats her web every night and respins it each morning, so maybe one day she just decides the effort is no longer worth it?
Wikipedia article on these guys, (or, more properly, ladies): http://en.wikipedia.org/wiki/Argiope_aurantia
Another good “zipper spider” article: http://aggie-horticulture.tamu.edu/galveston/beneficials/beneficial-24_spider_blackandyellow_argiope.htm